The present invention relates to proton conducting electrolytes which are prepared for use in intermediate temperature range fuel cells and other electrochemical devices that operate in the temperature range of between 200° C. to 600° C.
Proton conducting electrolytes are a core component of any electrochemical device based on proton conduction such as, for example, fuel cells, hydrogen separation and pumping devices, etc. It is well known that presently there are no proton conducting material with proton conductivity high enough to successfully operate in the intermediate temperature range (200-600° C.) when prepared by current material preparation techniques that result in an electrolyte layer at least 10 μm thick. The polymer based electrolytes, such as Nafion or PBI, are know to operate in a temperature of below 200° C., as a temperature above such destroys the polymer electrolyte. Perovskite ceramic electrolytes such as zirconates and cerates must operate at very high temperatures as their conductivities are not high enough until the temperature reaches approximately 600° C. Hence, no suitable electrolyte is found for the intermediate temperature range of between 200° C. and 600° C.
However, it is desirous to develop an electrolyte which may operate within the intermediate temperature range as it solves many outstanding problems of lower temperature systems, especially fuel cells, while avoiding high operating temperature induced mechanical and thermal mismatch problems. It thus is seen that a need remains for an intermediate temperature electrolyte and a method of producing such which overcomes problems associated with those of the prior art. Accordingly, it is to the provision of such that the present invention is primarily directed.